8 March 2008
Sakakibara R, Uchiyama T, Yamanishi T, Shirai K, Hattori T
Bladder dysfunction (urinary
urgency/frequency) and bowel dysfunction (constipation) are common
non-motor disorders in Parkinson’s
disease (PD). In contrast to motor disorder, the pelvic
autonomic dysfunction is often non-responsive to levodopa treatment.
Brain pathology mostly accounts for the bladder dysfunction
(appearance of overactivity) via altered dopamine-basal ganglia
circuit, which normally suppresses the micturition reflex. In
contrast, peripheral enteric pathology mostly accounts for the
bowel dysfunction (slow transit and decreased phasic
contraction) via altered dopamine-enteric nervous system circuit, which
normally promotes the peristaltic reflex. In addition, weak
strain and paradoxical anal contraction might be the results of
brain pathology.
Pathophysiology of the pelvic organ
dysfunction in PD differs from that in multiple system atrophy;
therefore
it might aid the differential diagnosis. Drugs to treat bladder
dysfunction in PD include anticholinergic agents. Drugs to
treat bowel dysfunction in PD include dietary fibers,
peripheral dopaminergic antagonists, and selective serotonergic
agonists.
These treatments might be beneficial not only in maximizing
patients’ quality of life, but also in promoting intestinal absorption
of levodopa and avoiding gastrointestinal emergency.
